package com.trilink.androidlib.widget;

import android.content.Context;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.os.Handler;
import android.os.Message;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.ImageView.ScaleType;
import android.widget.LinearLayout;

import com.nostra13.universalimageloader.cache.disc.naming.Md5FileNameGenerator;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import com.nostra13.universalimageloader.core.assist.QueueProcessingType;
import com.trilink.androidlib.R;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;


/**
 *  ViewPager实现的轮播图广告自定义视图，如京东首页的广告轮播图效果；
 * 既支持自动轮播页面也支持手势滑动切换页面
 * 
 *
 */
public class SlideShowView extends FrameLayout {
    //  使用universal-image-loader插件读取网络图片，需要工程导入universal-image-loader-1.8.6-with-sources.jar
    private ImageLoader imageLoader = ImageLoader.getInstance();
    //轮播图图片数量
    private final static int IMAGE_COUNT = 5;
    //自动轮播的时间间隔
    private final static int TIME_INTERVAL = 5;
    //自动轮播启用开关
    private final static boolean isAutoPlay = true;
    //自定义轮播图的资源
    private String[] imageUrls;
    //放轮播图片的ImageView 的list
    private List<ImageView> imageViewsList;
    //放圆点的View的list
    private List<View> dotViewsList;
    private ViewPager viewPager;
    //当前轮播页
    private int currentItem = 0;
    //定时任务
    private ScheduledExecutorService scheduledExecutorService;
    private Context context;
    //Handler
    private Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            // TODO Auto-generated method stub
            super.handleMessage(msg);
            viewPager.setCurrentItem(currentItem);
        }
    };

    public SlideShowView(Context context) {
        this(context, null);
        // TODO Auto-generated constructor stub
    }

    public SlideShowView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
        // TODO Auto-generated constructor stub
    }

    public SlideShowView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        this.context = context;
        initImageLoader(context);//������application�г�ʼ��
        initData();
        if (isAutoPlay) {
            startPlay();
        }
    }

    /**
     * 开始轮播图切换
     */
    private void startPlay() {
        scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();
        scheduledExecutorService.scheduleAtFixedRate(new SlideShowTask(), 1, 4, TimeUnit.SECONDS);
    }

    /**
     * ͣStop轮播图切换
     */
    private void stopPlay() {
        scheduledExecutorService.shutdown();
    }

    /**
     * 初始化相关Data
     */
    private void initData() {
        imageViewsList = new ArrayList<ImageView>();
        dotViewsList = new ArrayList<View>();
        // 异步任务获取图片
        new GetListTask().execute("");
    }

    /**
     *初始化Views等UI
     */
    private void initUI(Context context) {
        if (imageUrls == null || imageUrls.length == 0)
            return;
        LayoutInflater.from(context).inflate(R.layout.layout_slideshow, this, true);
        LinearLayout dotLayout = (LinearLayout) findViewById(R.id.dotLayout);
        dotLayout.removeAllViews();
        //热点个数与图片特殊相等
        for (int i = 0; i < imageUrls.length; i++) {
            ImageView view = new ImageView(context);
            view.setTag(imageUrls[i]);
            if (i == 0)//给一个默认图
                view.setBackgroundResource(R.drawable.pic_slide_show_view);
            view.setScaleType(ScaleType.FIT_XY);
            imageViewsList.add(view);
            ImageView dotView = new ImageView(context);
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
            params.leftMargin = 4;
            params.rightMargin = 4;
            dotLayout.addView(dotView, params);
            dotViewsList.add(dotView);
        }
        viewPager = (ViewPager) findViewById(R.id.viewPager);
        viewPager.setFocusable(true);
        viewPager.setAdapter(new MyPagerAdapter());
        viewPager.setOnPageChangeListener(new MyPageChangeListener());
    }

    /**
     * 填充ViewPager的页面适配器
     * 
     */
    private class MyPagerAdapter extends PagerAdapter {
        @Override
        public void destroyItem(View container, int position, Object object) {
            // TODO Auto-generated method stub
            //((ViewPag.er)container).removeView((View)object);
            ((ViewPager) container).removeView(imageViewsList.get(position));
        }

        @Override
        public Object instantiateItem(View container, int position) {
            ImageView imageView = imageViewsList.get(position);
            imageLoader.displayImage(imageView.getTag() + "", imageView);
            ((ViewPager) container).addView(imageViewsList.get(position));
            return imageViewsList.get(position);
        }

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return imageViewsList.size();
        }

        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
            // TODO Auto-generated method stub
            return arg0 == arg1;
        }

        @Override
        public void restoreState(Parcelable arg0, ClassLoader arg1) {
            // TODO Auto-generated method stub
        }

        @Override
        public Parcelable saveState() {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public void startUpdate(View arg0) {
            // TODO Auto-generated method stub
        }

        @Override
        public void finishUpdate(View arg0) {
            // TODO Auto-generated method stub
        }
    }

    /**
     *  ViewPager的监听器
     * 当ViewPager中页面的状态发生改变时调用
     * 
     */
    private class MyPageChangeListener implements OnPageChangeListener {
        boolean isAutoPlay = false;

        @Override
        public void onPageScrollStateChanged(int arg0) {
            // TODO Auto-generated method stub
            switch (arg0) {
            case 1://  手势滑动，空闲中
                isAutoPlay = false;
                break;
            case 2://  界面切换中
                isAutoPlay = true;
                break;
            case 0://  滑动结束，即切换完毕或者加载完毕
                // 当前为最后一张，此时从右向左滑，则切换到第一张
                if (viewPager.getCurrentItem() == viewPager.getAdapter().getCount() - 1 && !isAutoPlay) {
                    viewPager.setCurrentItem(0);
                }
                // 当前为第一张，此时从左向右滑，则切换到最后一张
                else if (viewPager.getCurrentItem() == 0 && !isAutoPlay) {
                    viewPager.setCurrentItem(viewPager.getAdapter().getCount() - 1);
                }
                break;
            }
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {
            // TODO Auto-generated method stub
        }

        @Override
        public void onPageSelected(int pos) {
            // TODO Auto-generated method stub
            currentItem = pos;
            for (int i = 0; i < dotViewsList.size(); i++) {
                if (i == pos) {
                    ((View) dotViewsList.get(pos)).setBackgroundResource(R.drawable.dot_focus);
                } else {
                    ((View) dotViewsList.get(i)).setBackgroundResource(R.drawable.dot_blur);
                }
            }
        }
    }

    /**
     *执行轮播图切换任务
     *
     */
    private class SlideShowTask implements Runnable {
        @Override
        public void run() {
            // TODO Auto-generated method stub
            synchronized (viewPager) {
                currentItem = (currentItem + 1) % imageViewsList.size();
                handler.obtainMessage().sendToTarget();
            }
        }
    }

    /**
     * 销毁ImageView资源，回收内存
     * 
     */
    private void destoryBitmaps() {
        for (int i = 0; i < IMAGE_COUNT; i++) {
            ImageView imageView = imageViewsList.get(i);
            Drawable drawable = imageView.getDrawable();
            if (drawable != null) {
                //解除drawable对view的引用
                drawable.setCallback(null);
            }
        }
    }

    /**
     * 异步任务,获取数据
     * 
     */
    class GetListTask extends AsyncTask<String, Integer, Boolean> {
        @Override
        protected Boolean doInBackground(String... params) {
            try {
                //  这里一般调用服务端接口获取一组轮播图片，下面是从百度找的几个图片
                imageUrls = new String[] { "http://imgsrc.baidu.com/forum/pic/item/09be3f094b36acaf0ad6eb717cd98d1000e99cde.jpg", "http://pic4.nipic.com/20091205/3779509_190419097063_2.jpg",
                        "http://hiphotos.baidu.com/%95%D7%D4%AA%B5%C0/pic/item/432e6436d9cd9b4deac4af86.jpg"};
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }

        @Override
        protected void onPostExecute(Boolean result) {
            super.onPostExecute(result);
            if (result) {
                initUI(context);
            }
        }
    }

    /**
     * ImageLoader 图片组件初始化
     * 
     * @param context
     */
    public static void initImageLoader(Context context) {
        // This configuration tuning is custom. You can tune every option, you
        // may tune some of them,
        // or you can create default configuration by
        // ImageLoaderConfiguration.createDefault(this);
        // method.
        ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(context).threadPriority(Thread.NORM_PRIORITY - 2).denyCacheImageMultipleSizesInMemory()
                .discCacheFileNameGenerator(new Md5FileNameGenerator()).tasksProcessingOrder(QueueProcessingType.LIFO).writeDebugLogs() // Remove
                                                                                                                                        // for
                                                                                                                                        // release
                                                                                                                                        // app
                .build();
        // Initialize ImageLoader with configuration.
        ImageLoader.getInstance().init(config);
    }
}